1. Field of the Invention
The present invention relates to telephone systems that offer privacy screening to their subscribers, and more specifically to allowing certain callers to by-pass the privacy screening.
2. Background of the Invention
A privacy screening service is a service that allows a subscriber to the privacy screening service to screen incoming calls. The privacy screening service provides information to the called party (in this case, the subscriber to the privacy screening service) that allows the subscriber to make an informed decision as whether or not to answer the call. For example, a subscriber may use the privacy screening service to block all unidentified calls from going through. Private telephone numbers are telephone numbers that block services such as xe2x80x9ccaller IDxe2x80x9d that would otherwise identify the caller to the called party. In telephone systems that offer private numbers and a privacy screening service to its customers, calls from a private number to a subscriber with the privacy screening service cannot be completed, unless the caller authorizes the system to override the privacy of his number. Similarly, a call from an unknown number (e.g., a call from outside the telephone network) would not be completed automatically.
FIG. 1 is a schematic diagram showing the basic architecture of an Advanced Intelligent Network telephone system. The Advanced Intelligent Network System is described in U.S. Pat. No. 5,701,301 and U.S. Pat. No. 5,838,774, which are hereby incorporated by reference. FIG. 1 shows the caller""s telephone 101 which is connected via the calling party""s voice line 102a to its Service Switching Point (SSP) 103. SSP 103 is connected via voice trunk 102b to a second SSP (SSP 104). SSP 104 is the SSP that services the called party""s telephone 105. In this example, the called party is a subscriber who has subscribed to the privacy screening service. (The called party will be referred to as the xe2x80x9csubscriberxe2x80x9d as well as the xe2x80x9ccalled partyxe2x80x9d herein.) FIG. 1 also shows a Signaling Transfer Point (STP) 106 that services a Service Control Point (SCP) 107 and a third SSP (SSP 108) that services a Service Node (SN) 109. SCP 107 has a database 107a that contains subscriber information.
STP 106 is a signaling hub that routes packets of data over the common channel signaling network. Common channeling signaling networks are data communications networks laid over the system""s switching network that carry data and control messages to and from and among the SSPs, STPs, and SCPs in the network. Signaling System 7 (SS7) is the protocol that runs over common channel signaling networks. A common channel signaling network using the Signaling System 7 protocol is often referred to as an SS7 network. The SS7 network carries data and control messages to the SSPs in the telephone network. SCPs are powerful fault-tolerant computers, e.g., ATandT Star Server FT Model 3200 or ATandT Star Server FT Model 3300 computers (these and more current computers such as the Advantage P200 and Advantage 4P200 models are presently available from Lucent Technologies). SCPs are xe2x80x9cintelligence centersxe2x80x9d with access to applications databases that enable the network to deliver advanced services such as caller ID, privacy screening and call forwarding. The SCPs also execute service package applications (SPAs) that deliver the advanced services. SNs are physically generally similar to SCPs, but include voice and Dual Tone Multi-Frequency (DTMF) signal recognition circuits, voice synthesizers, and voice recognition and digit collection capabilities. The operators of the telephone network can program their SNs to manage data, to respond to calls and to route calls as specified by the telephone network, and to collect digits from a caller or subscriber. The SN""s voice circuits can also be programmed to provide a voice response (e.g., to play pre-selected announcements) to callers and to perform voice recognition. SNs can also be programmed to respond to input from the callers by, e.g., further routing the call.
Key components of the AIN, such as the SCPs and STPs are generally provided in redundant pairs, such that the network does not experience an interruption while one of the components is down for repairs or servicing.
As shown in FIG. 1, STP 106 controls communications between SSPs 103, 104 and 108 and SCP 107. The SSPs are connected to the caller""s and the subscriber""s telephones and to each other via voice lines 102a and 102c and via voice trunks 102b and 102d. The SSPs communicate with STP 106 and SCP 107 via SS7 data links 110a, 110b, 110c and 110d. SN 109 is connected to SSP 108 by an Integrated Service Digital Network (ISDN) Basic Rate Interface (BRI) line 111.
When the caller places a call to the subscriber, the call is routed by SSP 103 to SSP 104. Because the subscriber has subscribed to the privacy screening service, that call (like all calls to that subscriber""s number) triggers a xe2x80x9ctermination attempt triggerxe2x80x9d or TAT. In response to the TAT, SSP 104 issues a query. The query goes up to SCP 107 via STP 106 asking for directions as to how the call should be terminated. The query includes the following information: the subscriber""s telephone number (in the called party field), the calling party""s telephone number (in the calling party field), the calling party""s presentation restriction indicator (also in the calling party field) and the trigger criteria type (indicating the service for which the query is intended).
SCP 107 checks the presentation indicator in the calling party number field of the query. If presentation of the caller""s number is not restricted, i.e., if the caller""s number is public, SCP 107 sends back a response instructing SSP 104 to terminate the call, and to supply the caller""s telephone number (and if the subscriber has subscribed to a higher level of service such as caller name deliveryxe2x80x94also referred to as caller ID deluxexe2x80x94the caller""s name and telephone number). In that case, SSP 104 terminates the call, i.e., completes the call, supplying the subscriber with the caller""s number (and possibly also with the caller""s name).
However, if the number of the calling party is unknown, the prior art system asks the calling party to record his or her name before routing the call to the subscriber. Routing the call to the subscriber generally requires a complex sequence of calls, queries and responses, thus burdening the network with additional traffic. Frequent callers, such as the subscriber""s close friends or family members (or the subscriber himself or herself, calling home), who call either from private numbers or from unknown numbers, would be unnecessarily screened each time they made calls to the subscriber. Such callers may find the unnecessary delays of having to listen to and respond to the privacy screening announcements very inconvenient.
Furthermore, a separate problem occurs with privacy screening when the subscriber is calling his own number (whether from a public, private or unknown telephone) to check or retrieve messages from his or her answering machine. Because the subscriber is not at home to accept the call, the call does not go through, and the privacy screening service prevents the subscriber from retrieving his or her messages. Privacy screening may also prevent the subscriber from calling home, when calling from a private or unknown telephone.
Privacy screening systems are described in U.S. patent applications Ser. Nos. 09/372,746 and 09/372,676 which are both incorporated herein by reference.
The present invention is a system and method that allows callers to bypass the subscriber""s privacy screening by entering a bypass code, thus avoiding the announcements described above, and allowing the subscriber to retrieve messages from his or her answering machine. The subscriber must provision a password (or personal identification number) and bypass code with the system administration prior to using his or her bypass code.
FIG. 2 is a schematic diagram showing how calls are routed for a first embodiment of the present invention, when the calling party number is private or unknown. When a calling party dials the subscriber""s number, the call is routed through the calling party""s SSP 103 to the subscriber""s SSP 104 (call 1 in FIG. 2). Because the subscriber""s number is provisioned with a termination attempt trigger, the call triggers a query from SSP 104 to SCP 107 via STP 106 (query 2 in FIG. 2). SCP 107 checks the presentation indicator in the calling party number field of the query, and determines that the number is either private or unknown. It then sends a response to SSP 104 (response 3), instructing SSP 104 to forward the call to SN 109. SSP 104 then forwards the call (call 4) to SN 109 via the SN""s SSP, SSP 108. When SN 109 gets the call, it plays an announcement to the calling party. At this point, a caller provided with a bypass code can enter the bypass code.
Preferably, the caller can enter his or her bypass code at any time after the announcement starts, i.e., the caller can interrupt the announcement. SN 109 collects the digits entered by the calling party (i.e., it collects the bypass code assuming the caller entered the correct bypass code), and then dials a Customized Dialing Plan (CDP) code(e.g., *99) with the called party number, the calling party number, and the digits entered by the caller attached to the CDP code. For example, if the CDP code is *99, and the digits (i.e., the bypass code) entered by the caller is 1234, SN 109 would dial *99 (called party number)(calling party number)1234. The CDP code prompts an Info_Analyzed query from SN 109""s SSP (SSP 108) to SCP 107 via STP 106 (query 6 in FIG. 2). SCP 107 then checks its database 107a and confirms that the calling party entered the correct bypass code (i.e., the SCP checks that the entered digits match the subscriber""s bypass code), and sends an Analyze_Route response authorizing termination of the call (response 7).
SSP 108 then makes an outbound call (call 8 in FIG. 2), with the calling party""s number in the calling party field (as set by this SCP), the subscriber""s number in the called party field and the SN""s number in the charge number field. This call triggers a second TAT at SSP 104, prompting a query (query 9) from SSP 104 to SCP 107. SCP 107 recognizes the SN""s number in the charge number field, and authorizes termination of the call (response 10). The call is then terminated from SSP 104 to the subscriber (call 8xe2x80x2). The SCP does not change the calling party""s characteristics, i.e., if the calling party number is included with the CDP code, the SCP will retain the call as xe2x80x9cpresentation restricted.xe2x80x9d Otherwise, the calling party number will be all 1""s, which would indicate that the call is from an unknown number.
FIG. 3 is a schematic diagram of a second embodiment of the present invention. The second embodiment starts off (like the first embodiment) with the calling party dialing a call from an unknown or private number to the subscriber (call 1 in FIG. 3). Because the subscriber has privacy screening, this call triggers a TAT query from SSP 104 to SCP 107 (query 2 in FIG. 3). In this second embodiment, the SCP responds to the TAT query from SSP 104 (after determining that the calling party is unknown or private) by sending a Send_To_Resource message (response 3 in FIG. 3) to SSP 104, instructing SSP 104 to play an announcement to the calling party, asking the calling party to record his or her name or number. As in the first preferred embodiment, the announcement is interruptible. If the calling party enters digits during the announcement, SSP 104 collects the digits and sends a Resource_Clear query with the digits (i.e., the bypass code if the caller entered the correct bypass code) in the Collected_Digits field to SCP 107 (query 4 in FIG. 3). SCP 107 then checks the entered and collected digits against the bypass code stored in its database. If the calling party entered the correct bypass code (i.e., if SCP 107 determines that the entered and collected digits matches the subscriber""s bypass code), SCP 107 sends an Analyze_Route response authorizing termination of the call (response 5 in FIG. 3). The call is then terminated to the subscriber (call 1xe2x80x2 in FIG. 3), without any changes to the presentation indicator or to the calling party number.
The second embodiment of the present invention is conceptually simpler, and does not require as many calls and messages to be exchanged as is required by the first embodiment, because SN 109 is never involved in the call routing. The main difference between the first and the second embodiments is that the first embodiment uses the SN to conduct a dialog with the caller, whereas the second embodiment uses the subscriber""s SSP to conduct the dialog. Thus, in the second embodiment, each and every SSP in the network must be programmed, whereas in the first embodiment the programming resides in the SNs. Because there are many more SSPs that would have to be programmed than SNs, and because the SSPs may well be provided by different vendors (which would require different programming), and because the operator of the telephone system has full control over the SNs, but must work with its vendors to implement any change in the SSPs, the simplicity advantage of the second embodiment may well be outweighed by the greater ease of implementation of the first embodiment.
A third embodiment of the present invention, like the first embodiment, uses a CDP code to allow a caller from a private or unknown telephone to enter a pass code to bypass privacy screening. This embodiment will be described with reference to FIG. 3a. The call sequence will be described first for calls from private numbers and then for calls from unknown numbers. FIG. 3a applies equally to both calls from private and from unknown callers.
As shown in FIG. 3a, when a calling party dials the subscriber""s telephone number, the call (call 1) is routed from the calling party""s SSP 103 to the subscriber""s SSP 104, prompting a termination attempt query (query 2) to SCP 107. SCP 107 checks the presentation indicator on the calling party number, and discovers that the indicator is xe2x80x9cPresentation Restrictedxe2x80x9d, and responds (response 3) by instructing SSP 104 to forward the call (call 4) to SN 109 via SSP 108. SN 109 then plays an announcement to the calling party (through SSPs 108, 104 and 103), asking for permission to present the calling party""s telephone number to the subscriber. If the calling party then enters a 4-digit pass code, SN 109 sends a data request to SCP 107 over data link 120 with the subscriber""s telephone number, and SCP 107 retrieves the pass code corresponding to the subscriber""s telephone number from its database, and sends that pass code to SN 109. Data link 120 is a direct data link, e.g., an X.25 or TCP/IP link between SN 109 and SCP 107. SN 109 checks the pass code received from SCP 107 against the pass code entered by the calling party. If the bypass codes do not match, the call is treated as a normal call from a private telephone number.
If the bypass codes match, SN 109 dials a string starting with a CDP code, e.g., CDP code Y (generally, a two-digit code), followed by the subscriber""s number, the calling party number, and, e.g., a five digit string of 2""s (22222). The CDP code Y triggers a query, e.g., an Info_Analyzed query (query 5) at the SN""s SSP 108. SCP 107 then returns an Analyze_Route message (response 6) with the subscriber""s number as the CdPN, and the calling party number as the CgPN. SSP 108 then calls the subscriber with the lead number for the SN (e.g., the SN""s multi-line hunt group (MLHG) number) as the charge number (call 7). When the call reaches the subscriber""s SSP 104, it prompts a TAT query to SCP 107. SCP 107 recognizes the SN""s MLHG number in the charge number field, and responds with an Authorize_Termination message to SSP 104. SSP 104 then terminates the call (call 1xe2x80x2) to the subscriber, using the CNAME TR-1188 generic requirements.
FIG. 3a also applies when the caller is calling from an unknown telephone number. In that case, when the termination attempt query (query 2) reaches SCP 107, SCP 107 determines that the calling party number is unavailable. SCP 107 then instructs (response 3) SSP 104 to forward the call (call 4) to SN 109, with the SN""s MLHG number in the CdPN field and the calling party number in the CgPN field. SN 109 then plays an announcement to the calling party, asking the calling party to record his or her name. If the caller enters a four-digit pass code, SN 109 sends a data request message to SCP 107 with the subscriber""s telephone number over the direct data link 120 between SN 109 and SCP 107. SCP 107 responds to the data request message by retrieving the subscriber""s telephone number from the data request, and retrieving the bypass code corresponding to the subscriber""s telephone number from its database, and sending that bypass code to SN 109 over data link 120. If SCP 107 cannot find a pass code corresponding to the subscriber""s telephone number, it sends a message to SN 109, that it could not find the pass code, and the call is treated as a normal call from an unknown telephone number.
If SCP 107 does find the bypass code, when SN 109 receives the response from SCP 107, it checks the pass code received from SCP 107 against the pass code entered by the calling party. If the pass codes do not match, the call is treated as a normal call from an unknown telephone number.
If the pass codes match, SN 109 then dials a CDP code Y, followed by the 10-digit called party number (the subscriber""s number) and, e.g., a 10-digit string of 1""s. This ensures that the call will be terminated to the subscriber without any privacy modifications. The call reaches SSP 108 and SN 109 drops out of the call. The CDP code Y triggers a query (query 5) to SCP 107, with Y (e.g., *95) as the Access Code and the rest of the dialed digits in the Collected_Digits field. SCP 107 then analyzes the digits, and returns a response (response 6) with the subscriber""s number as the CdPN, and a bogus number (i.e., a number that is not allowed by the telephone network) as the CgPN (with the presentation indicator set to xe2x80x9cunavailablexe2x80x9d).
SSP 108 then calls the subscriber with the subscriber""s number in CdPN field, the bogus number in the CgPN field (with the presentation indicator set to xe2x80x9cunavailablexe2x80x9d) and the charge number as the lead number for the SN""s MLHG number. When the call (call 7) reaches the subscriber""s SSP 104, it hits the TAT provisioned on the subscriber""s number at SSP 104. SSP 104 then sends a termination attempt message to SCP 107 with the bogus number as the CgPN (presentation indicator set to unavailable), the subscriber number as the CdPN, and the SN""s MLHG number in the charge number field. SCP 107 recognizes the SN""s MLHG number in the charge number field, and sends an Authorize_Termination message to SSP 104 with the bogus number in the CgPN and the presentation indicator set to xe2x80x9cunavailable.xe2x80x9d SSP 104 then terminates the call to the subscriber (call 1xe2x80x2), using the CNAME TR-1188 generic requirements.
The present invention preferably allows a subscriber to access the system administration to change his or her bypass code (including when the subscriber is calling for the first time, to change his or her bypass code from a default bypass code provided by the system).
In a first preferred embodiment for allowing the subscriber to access the system administration, the subscriber is provided with a system administration telephone number, a password or personal identification number (PIN), and a default bypass code. The system administration number is a telephone number at the service node. Thus when the subscriber calls SN 109 using that telephone number, the call is routed from the subscriber through the subscriber""s SSP 104 to the SN""s SSP 108 (call 1 in FIG. 4a).
The system administration telephone number at SN 109 has a TAT assigned to it. When the call from the subscriber comes in to the SN""s SSP 108, the call triggers a TAT query from SSP 108 to SCP 107 via STP 106 (query 2 in FIG. 4a). SCP 107 then checks its database 107a to see if the current call is the first call made by the subscriber to the system administration, e.g., it checks to see if the xe2x80x9cfirst cal1xe2x80x9d flag for that subscriber is still xe2x80x9con.xe2x80x9d If the first call flag is still on, SCP 107 sends an Authorize_Termination message (response 3) to SSP 108, authorizing termination of the call from the subscriber to a system administration telephone number at SN 109 for first-time callers (e.g., a multi-line hunt group telephone number that services first-time callers to the privacy screening manager at the SN). For first-time callers, the Display_Text field is populated with a default password and passcode, which SN 109 retrieves. SN 109 then verifies the password and passcode entered by the subscriber against the default password and passcode. Once the call reaches SN 109, SN 109 plays a series of announcements for a subscriber calling for the first time, e.g., SN 109 asks the subscriber to enter his or her password and the default bypass code. SN 109 then asks the subscriber to enter a new bypass code (and generally asks the subscriber to also confirm the new bypass code). First-time callers are only allowed to change their pass code and password from their home telephones. The number of the home telephone is obtained by SN 109 from the last re-directing party number.
If the first call flag is not on, SCP 107 sends an Authorize_Termination message to SSP 108 (FIG. 4a also applies in this casexe2x80x94this is response 3 in FIG. 4a), authorizing termination of the call from the subscriber to a system administration telephone number at SN 109 for non-first-time callers (e.g., a multi-line hunt group telephone number that services non-first-time callers to the privacy screening manager at the SN). The response from SCP 107 also sends the subscriber""s bypass code and password to SN 109 in the Display_Text field of its response. Once the call (call 1xe2x80x2) reaches SN 109, SN 109 plays an announcement to the caller, asking the caller to enter his or her password and bypass code. SN 109 then compares the password and bypass code received from SCP 107 to the password and bypass code entered by the caller. If the passwords and bypass codes do not match, the caller is given a second opportunity to enter the correct password and bypass code. If the password and bypass code do not match the second time, the call is disconnected.
If the subscriber enters the correct password and bypass code, SN 109 plays an announcement asking the subscriber if he or she would like to change his or her bypass code. If the subscriber indicates that he or she would like to change his or her bypass code, SN 109 collects the changed bypass code from the subscriber through a series of announcements, described below with reference to FIG. 7a. It then dials a CDP code, e.g., *99 followed by the subscriber number, the changed bypass code, and the password. The CDP code triggers an Info_Analyzed query from SSP 108 back up to SCP 107 (query 4), with the subscriber""s password and changed bypass code in the collected digits field of the query. SCP 107 receives the changed bypass code, and changes the bypass code for that subscriber in its database 107a. SCP 107 then responds to the query by instructing SSP 108 to disconnect the call (response 5), i.e., by sending a disconnect message to SSP 108.
A second preferred embodiment for allowing the subscriber to access the system administration, uses a PODP (public office dialing plan) trigger provisioned on the SN""s SSP to query the SCP""s subscriber database. A subscriber who has never provisioned his or her service with a bypass code and password must call the administration system number from his or her home telephone. Subscribers who have already provisioned their bypass code and password may call from any telephone (for example, if they want to change the bypass code).
When the subscriber calls the system administration number (call 1 in FIG. 4b), the PODP trigger provisioned on the SSP serving the system administration (SSP 108) prompts an Info_Analyze query (query 2 in FIG. 4b) to SCP 107. SCP 107 checks that the called party was the system administration, then instructs SSP 108 (response 3 in FIG. 4b) to forward the call to the system administration number (call 4), which is an MLHG that terminates at the SN that holds the privacy director""s SPA (service package application). SN 109 checks the called party number, and determines that the call was to the system administration. SN 109 asks the subscriber if he or she is calling from his or her home telephone. If the call is not from the subscriber""s home telephone, SN 109 asks the subscriber for his or her home telephone number. SN 109 then retrieves the subscriber""s subscription data from SCP 107 (query 5 and response 6 over data link 120), based on the subscriber""s number as the calling party number. If there are no subscription data for the subscriber number, the subscriber is asked to call a service representative for assistance. If there are subscriber data for the subscriber number, and the subscriber is calling for the first time, the subscriber is required to provision his or her password and bypass code. If there are subscriber data for the subscriber number, and the subscriber is not calling for the first time, the subscriber is provided with the option of changing his or her password and/or bypass code. Preferably, data link 120 is an X.25 connection. SN 109 then sends X.25 HB messages to SCP 107 so that SCP 107 can monitor the condition of SN 109. (X.25 HB messages include a mechanism that ensure that there is connectivity between the SN and the SCP.) Data link 120 could also be a TCP/IP connection, as shown on FIG. 4b. 
If the subscriber enters an invalid password, SN 109 plays an error announcement. Preferably, the subscriber is only given one second chance to enter the correct password.
The present invention is described herein and shown in the drawings as having one SCP (representing a pair of redundant SCPs) and one SN. However, the present invention could be implemented using more than one SCP and/or SN.
Accordingly, it is an object of the present invention to provide a bypass code that could be used by callers to a subscriber to a privacy screening service that would allow the subscribers to bypass the privacy screening service.
It is another object of the present invention to allow subscribers to a privacy screening service to bypass the privacy screening service when they are calling to check if any messages have been left for them on their answering machines or voicemail.
It is another object of the present invention to minimize the burden on an advanced intelligent network by reducing some of the delays that can occur in calls from private or unknown numbers to subscribers to a privacy screening service.
It is another object of the present invention to provide a subscriber with means for changing his or her bypass code without having to contact a system administrator.